A Chicago violinist who’s a rising star in classical music, has a double life. It will be on display Sunday in Millennium Park as part of the Great Performers of Illinois festival.

This is the kind of music you normally associate with Rachel Barton Pine. She’s played violin with orchestras around the world. She’s got a foundation to help kids get started playing classical music themselves.

And she’ll take the stage Sunday to perform with a baroque trio and the Illinois Symphony Orchestra.

But then she’ll go change her outfit. And she’ll return in a lot of black and a lot of leather.

Barton Pine isn’t just a famous classical violinist. She’s a member of the doom-thrash band, Earthen Grave. Doom is a form of heavy metal that’s ponderous and full of foreboding. Thrash is its opposite: fast and frantic. Earthen Grave combines the two, with Barton Pine’s violin woven throughout.

Quite a change for a woman who was a child prodigy playing classical violin. She says she didn’t listen to rock until she got a transistor radio at age 11.

And she heard Guns N’ Roses.

BARTON PINE: It was in a minor key, and it had a little more edge and aggression, and there was something about it that was so powerful and made you feel like you could go out and conquer the world.

But it didn’t occur to her to play rock on her violin until she played the national anthem at a Bulls game.

BARTON PINE: I started getting total strangers coming up to me on the street saying, wow, I didn’t realize violins were so cool. Maybe they’d heard pretty violin music like Pachelbel’s Canon in a dentist waiting room or hotel lobby and they thought the violin was kind of sleepy and boring. Well, that would be like if you heard some light rock ballad and you thought that represented all of rock music.

Barton Pine started playing music like this on rock radio stations. She did it to prove that violins and classical music could rock.

BARTON PINE: But I never wanted to plug in a violin, because I’d spent my life working on creating a beautiful sound on the acoustic violin, and I thought why would I take all of that work and run it through an amp and mess it up?

But then, a friend invented a new kind of electric violin.

BARTON PINE: And it straps onto the body, so it’s head free and you could head bang when you play metal.

And head bang she does.

Earthen Grave’s bass player, Ron Holzner, says other rock bands have featured electric violin. But the band wants to treat violin like a lead guitar.

HOLZNER: We included the violin, and these songs just became something tremendous, actually. They grew, and they grew wonderfully.

He remembers when Barton Pine saw a mosh pit form from the stage.

HOLZNER: I saw the look in Rachel’s face, and ran over and she was, My first mosh pit, aaah, she was so excited. I thought she was scared or nervous. The excitement in her face was so cool.

BARTON PINE: It’s like taking what I enjoy about being in the crowd at a metal show and head banging and singing along and throwing the horns, and all of that, and taking that to the stage, where it’s twice as fun to actually be the one doing it. You get to just absolutely go crazy.

Barton Pine started out wanting to introduce classical music to rock audiences. She didn’t expect it could work the other way, too. But now at Earthen Grave shows, she’s seeing friends from the classical world in the crowd.

NOTE: The free concert starts at 7 Sunday night at Millennium Park. It’s part of the three-day Great Performers of Illinois festival that begins Friday.